If you were looking for the best way to make Britain's railways safer you would not start from here. Desperate efforts to improve safety and restore credibility in train travel a year after the Paddington disaster have uncovered a system racked with confusion and neglect.

All the technological solutions currently on offer to stop trains shooting red signals are flawed, and the 1 billion passengers that use the network every year have been left without the fullest possible protection as wrangling continues.

Tomorrow, Railtrack, which owns the lines, signalling and stations, will respond to a legal challenge by the train drivers' union Aslef calling on the company to scrap its plans to install an inferior safety system. Railtrack will tell the official inquiry investigating safety in the wake of Paddington, and the Southall crash of 1997, that it is pressing ahead with the project to install a non-computerised device called TPWS, with government backing.

Successive UK governments and the rail industry have dragged their heels for so long that the computerised Automatic Train Protection (ATP) equipment they were expected to fit a decade ago is now out of date.

Safety campaigners and the unions are at loggerheads with Railtrack, the train operators, the safety authorities and the Government.

A new generation of technology called the European Train Control System (ETCS) is being furiously developed on the Continent and Britain is involved, but it is not yet ready to be installed. Railtrack and the engineering firm Alstom have been working on ETCS with Siemens of Germany, France's Alcatel, Italy's Ansaldo and various European Union national railway companies. The new system will be compatible across Europe but adapted to fit each national network. Many continental operators are busy signing up for it.

Railtrack is poised to sign a £1 billion contract with Alstom later this year for new signalling on the West Coast mainline that will provide new-generation train safety between London, the Midlands and Glasgow by 2005.

But beyond the West Coast line there are currently no definite plans or a timetable to order this technology for the rest of the UK network or even just its mainlines.

Robin Gisby, Railtrack's network development director, said: 'After West Coast, the East Coast [line] would be next. We are maybe looking at 2006/7, then Great Western, if they are [due for] the next big upgrades.

'It is very difficult to build this new system into the existing patchwork of signalling.'

Gisby said the company would 'think carefully' about possibly 'retro-fitting' the new system on the existing London-Brighton route or the Midland mainline, which runs via the East Midlands to Yorkshire, 'if we were not going to be upgrading them in the next couple of years'.

Words like that prompt industry observers to warn it will be at least a decade before Britain has a decent high speed rail network with automatic safety systems.

The Hidden Inquiry into the 1988 Clapham crash, which killed 35 people, recommended that ATP be fitted within five years to eliminate the high number of signals passed at danger (spads). The then Transport Secretary, Cecil Parkinson - a railwayman's son - promised the House of Commons in November 1989: 'Finance will not stand in the way of the implementation of the report.' He was backed by his Labour Shadow, John Prescott.

But Parkinson, who called for speedy action, had moved to another job by the time his Conservative government colleagues and British Rail shelved the plans in 1994 - on financial grounds.

They calculated that, with a £550 million price tag, ATP would cost up to £14m for each potential life it saved. Investment on the railways is usually limited to £2m per saved life. Safety spending on the roads, where more than 3,400 people are killed annually, is around £750,000 per life.

While other EU states were modernising their railways in the Nineties, building new high-speed lines and fitting them with ATP, Britain limited its work to the Heathrow Express and the Channel Tunnel, and pushed through privatisation while the bulk of the network crumbled.

Only limited ATP pilot schemes were ever introduced. Great Western notoriously had the system installed but not working, because of reliability problems, when its Swansea to London train went through a red light and smashed into a freight train at Southall, killing seven people.

Carol Bell, who was injured and traumatised in that crash and is now a safety campaigner, is convinced that existing versions of ATP in use in Britain, other parts of Europe and the US should have been fitted throughout this country a long time ago - and still could be. She is supported by Mick Rix, general secretary of Aslef, which has launched the legal challenge to TPWS currently being aired at the inquiry.

Bell is dismayed at the failure to fit ATP, compounded by the distinct lack of commitment to signing up for the new European system for the whole network.

Campaigners dread that once TPWS is fitted, the industry will try to wriggle out of upgrading to the European system - even if the Cullen Inquiry into Paddington recommends it, European law encourages it and the Government provides cash towards the £2bn cost.

'The sad thing is that "only" seven people died at Southall and although 31 deaths at Paddington was dreadful, if it had been the 200 feared at one point then I think there would have been drastic action on safety systems by now,' said Bell.

Louise Christian, the solicitor leading the legal battle for the victims of both crashes, said TPWS should be scrapped in order to ensure the most expedient installation of the new European systems.

But Sir David Davies, whose report on safety written earlier this year for the Government and accepted by Prescott as Deputy Prime Minister, said: 'The European system for the whole country would take at least nine years to fit, and most people say 15. TPWS can save lives sooner.'

Safety campaigners warn there will have to be another crash before the warring parties agree about the best solution, let alone implement it.

How the train protection systems compare

Automatic Train Protection (ATP)

How it worksGeneric term for computer-based automatic system.

UK version consists of electronic messages from signalling system sent via cables in track or lineside unit to computer on train. Computer tells driver maximum safe speed based on route, speed limits, red signal ahead, etc. If permitted speed is exceeded, brakes are applied automatically.

Up and running?Some form of ATP operating in most EU states. UK has ATP on part of Great Western and Chiltern lines, Heathrow Express and Eurostar trains in Channel Tunnel.

Pros98 per cent prevention of accidents caused by signals passed at red.

ConsExisting ATP in UK cannot be upgraded to match forthcoming European systems. Difficult and expensive to fit to old trains, less reliable. Could take five-15 years.

CostEstimated between £550 million and £2 billion to fit whole network.

European Train Control System (ECTS)

How it worksThree levels of fully automatic system linking signalling system to onboard computer. Level One overlays existing signals and transmits data to train giving full ATP up to 180mph. Level Two has improved radio communications capability.

Level Three does away with lineside signal and data kit. Train controlled via secure, digital radio links. Line capacity increased as trains can run closer together.

Up and running?Level two currently being fitted to Vienna-Budapest line. Planned for UK West Coast Line by 2005. Further testing planned in Switzerland, France, Italy, Germany and Spain.

ProsState of the art train protection and communications. Complies with new EU laws.

ConsDifficult to retro-fit, therefore usually installed only when lines upgraded.

CostEstimated £1.1billion-£2bn.

Train Protection and Warning System (TPWS)

How it worksCable loops in track transmit radio signals to unit in driver's cab. Brakes are automatically applied if train shoots red signal or goes too fast through speed trap set in advance of signal. Enhances existing UK Automatic Warning System (AWS) that rings bell in cab for green signal, sounds horn for yellow or red, applying brakes if driver does not respond.

Up and running?Small-scale trials on part of Thameslink line since 1997. Plans to fit TPWS to all signals at junctions by the end of 2002, and to virtually all rolling stock by the end of 2003. Proposals to trial enhanced system for speeds up to 100mph.

ProsQuicker, easier and cheaper to fit than ATP. Reasonably reliable.

ConsCurrent system only effective up to 75mph. TPWS cannot be upgraded to meet new European standards.